This invention relates to water dispersible, stable, solid products or formulations of selected starches, active agricultural agents, and surfactants and/or adjuvants. These solid products are readily water soluble or dispersible. Furthermore, these products have a starch matrix or carrier structure which changes the physical form of the product, makes it compatible when dispersed, allows for a high loading of active material and permits use of a broad range of surfactants, adjuvants and other ingredients. Furthermore and surprisingly, it has been found that such starch containing agrochemical products can exhibit increased biological efficacy of the active material.
Various formulations of agricultural active ingredients have been developed to satisfy the needs for agricultural crop protection and other related areas. Oftentimes these products have been in the form of liquid formulations.
Recently, in crop protection formulation technology there has been a desire to move away from liquid formulations to solid products such as dry granules or powders. Such solid products would reduce the use of solvents, be more environmentally friendly and reduce transportation costs. However, the ability to provide solid products using a combination of active ingredients such as glyphosate, and surfactants such as polyoxyethylene sorbitan esters, e.g. Tween 20, has been difficult because such materials are not compatible and are not easy to process or work with. Although much effort has been made to develop solid agricultural products, most of the useful solid, starch based products exhibit extended or delayed release characteristics.
U.S. Pat. No. 6,228,807 issued on May 8, 2001 to M. Kuchikata et al, discloses dry, water-soluble herbicidal compositions of glyphosate with selected surfactants. While such compositions are water dispersible, it is difficult to form compatible solutions since many surfactants are not compatible with glyphosate in concentrated form.
Despite the various disclosures of active agricultural products, including the recent ""807 patent noted above, and solid products showing extended release properties, there is still the need for solid agricultural type products which are water dispersible, compatible when dispersed and exhibit quick release characteristics.
Accordingly, what is desired for use in agricultural applications, is a stable, solid product which has quick release properties, provides high load of active materials and can combine multiple components into a compatible system.
Now it has been found that stable, water dispersible solid products of agricultural active agents are provided when combined with selected starches and optionally surfactants and/or adjuvants.
More particularly, this invention is directed to a stable, dry solid formulation which is water dispersible and provides a rapid, compatible, homogeneous dispersion and comprises:
a) a chemically modified starch,
b) a biologically active agricultural material, and optionally
c) a surfactant and/or adjuvant.
This invention further involves agrochemical formulations containing combinations of two or more active materials.
This invention involves stable, water dispersible solid products of selected starches, agricultural active agents, and surfactants and/or adjuvants. These dry solid products or formulations are rapidly dispersed in aqueous medium, compatible when dispersed and provide quick release of the bioactive agent. These formulations also provide a high loading of the active ingredient and have been found especially useful in agricultural crop protection. Furthermore, the solid product of this invention has a starch matrix which allows for the use of one or more different active materials and the use of a wide variety of surfactants, adjuvants and other ingredients while still providing a compatible dispersion and high load capacity.
Stable, solid products are those where there is no bleeding or separation of individual components. Generally a product is considered stable when this condition exists for at least six months.
Dispersible, solid products are those which are functionally uniform or homogeneous when dispersed. The dispersed or water solubilized product may be in the form of a solution, emulsion or suspension.
Compatible solutions are those where the individual components remain homogeneous in the final aqueous solution. Compatible emulsions in water are those that remain stable, do not coalesce, phase out or separate, flocculate, aggregate or produce sediment. For compatible suspensions in water, the solids remain homogeneously suspended in the end use dispersion, i.e. they do not drop out. The compatible solutions or dispersions provide relatively or functionally uniform distributions of the components in the end use liquid. Compositions are typically considered compatible when these conditions exist for at least 4 hours and more particularly 24 hours or more.
Rapidly or readily dispersible is defined as a mixture with cold water and minimal agitation that gives a dispersion in less then 10 minutes, more particularly less then 3 minutes.
Solid products are those such as the type having a particulate form or structure and having a wide range of sizes and shapes, such as powders, granules (dust free powders), flakes, chips, sheets, tablets, pellets, agglomerates, etc.
The solid product or formulation of this invention will comprise either the combination of starch, active material and surfactant and/or adjuvant; starch and active material; or starch and surfactant and/or adjuvant. Any of the above formulations may also include optional additive ingredients.
The active ingredients used in the system or formulations of this invention include a broad range of materials and this includes active ingredients some of which don""t form free standing powders on their own. Some of the useful active materials may be liquid while others may be solids with low or high melting points. Particularly useful active ingredients for this invention are liquids at room temperature or low melting (e.g.  less than 80xc2x0 C.) materials and high melting (e.g.  greater than 80xc2x0 C.) crystalline materials.
The agricultural active agents which are used in the formulations of this invention can be any one or more of a wide range of water dispersible agrochemically active materials. Description of the actives as water dispersible means that they are water soluble or can be suspended or emulsified in water. More particularly, it may be one or more herbicides, pesticides, for example insecticides, fungicides, acaricides, nematocides, miticides, rodenticides, bactericides, mollusicides and bird repellants, and/or plant growth regulators. Especially useful active materials are herbicides, insecticides and fungicides. Usually, the active material will be a water insoluble or immiscible material, although granules can be made including water soluble active materials. Specific examples of active materials include:
Herbicides such as 6-chloro-N-ethyl-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine (common name atrazine); N,Nxe2x80x2-bis(1-methylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine (common name prometryn); substituted ureas such as diuron or Nxe2x80x2-(3,4-dichlorophenyl)-N,N-dimethylurea); sulfonyl ureas such as metsulfuron-methyl{2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) amino]carbonyl]amino]sulfonyl]benzoate}; triasulfuron {2-(2-chloroethoxy)-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide}; tribenuron-methyl {methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2yl)-methylamino]carbonyl]amino]sulfonyl]benzoate} and chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl] benzenesulfonamide}; bis-carbamates such as phenmedipham or {3-[(methoxycarbonyl)amino] phenyl (3-methylphenyl)carbamate}, aryloxyalkanoic acids like [(3,5,6-trichloro-2 pyridinyl)oxy] acetic acid (commonly known as triclopyr) and its salts or esters like triclopyr-triethanolammonium, triclopyr-butotyl, (2,4 dichlorophenoxy) acetic acid (commonly known as 2,4-D) and its salts or esters like 2,4-D butyl, 2,4-D-dimethylammonium, 2,4-D-diolamine, 2,4-D-2-ethylhexyl, 2,4-D-isooctyl, 2,4-D-isopropyl, [(4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)oxy] acetic acid (commonly known as fluoropyr) and its esters like furoxypyr-meptyl and fluroxypyr-2-butoxy-1-methylethyl, 2-(4-aryloxyphenoxy) propionic acids like butyl (xc2x1)-2-[[5-(trifluoromethyl) 2 pyridinyl]oxy]phenoxy]-propanoate (commonly known as fluazifop-butyl), (xc2x1)-2-[4-[[3-chloro-5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy]propanoic acid (commonly known as haloxyfop) and its esters haloxyfop-etotyl, haloxyfop-methyl, haloxyfop-P-methyl, butyl (R)-2-[4-(4-cyano-2-fluorophenoxy) phenoxy]propionate (commonly known as cyhalofop-butyl), cyclohexanedione oximes like (xc2x1)-(EZ)-2-(1-ethoxyiminobutyl)-5-[2-(ethylthio)propyl]-3-hydroxycylohex-2-enone (commonly known as sethoxydim). Additional useful herbicides include alpha-chloro-2xe2x80x2,6xe2x80x2-diethyl-N-methoxymethyl acetanilide (commonly known as alachlor), N-butoxymethyl-alpha-chloro-2xe2x80x2,6xe2x80x2-diethylacetanilide (commonly known as butachlor), 2xe2x80x2-methyl-6xe2x80x2-ethyl-N-(1-methoxy-prop-2-yl)-2-chloroacetanilide (commonly known as metolachlor), isobutyl ester of (2,4-dichlorophenoxy) acetic acid, 2-chloro-N-(ethoxymethyl)-6xe2x80x2-ethyl-o-acetotoluidide (commonly known as acetochlor), 1-(1-cyclohexen-1-yl)-3-(2-fluorophenyl)-1-methyl urea, S-2,3,3-trichloro-allyl-diisopropyl thiocarbamate (commonly known as triallate), and alpha, alpha, alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (commonly known as trifluralin).
Fungicides such as thiocarbamates, particularly alkylenebis(dithiocarbamate)s, for example maneb or {[1,2-ethanediylbis-[carbamodithiato] (2-)] manganese} and mancozeb or {[[1,2-ethanediyl-bis[carbamodithiato]](2-)] manganese mixture with [[1,2-ethanediylbis[carbamodithiato]] (2-)]zinc}; strobilurins such as azoxystrobin (methyl (E)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-a-(methoxymethylene) benzeneacetate} and kresoxim-methyl {(E)-a-(methoxyimino)-2-[(2-methylphenoxy)methyl]benzylacetic acid methyl ester}; dicarboximides such as iprodione {3-(3,5-dichlorophenyl)-N-isopropyl-2,4-dioxoimidazoline-1-carboxamide}; azoles such as propiconazole or {1-[2-(2,4-dichloro-phenyl)-4-propyl-1,3-dioxolan-2-yl-methyl-1H-1,2,4-triazole and tebuconazole or {(RS)-1-p-chlorophenyl-4,4-dimethyl-3-(1H-1,2,4-triazole-1-ylmethyl)-pentan-3-ol}; halophthalonitriles such as chlorothalonil pr {2,4,5,6-tetrachloro-1,3-dicyanobenzene}; and irorganic fungicides such as copper hydroxide or Cu(OH)2.
Insecticides including benzoyl ureas such as diflubenzuron or N-[[(4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide; carbamates including solid and liquid forms such as carbaryl or 1-naphthyl methyl carbamate, aldicarb, methomyl, carbofuran, bendiocarb, oxamyl, thiodicarb, trimethylcarb; organophosphates e.g. malathion, parathion, demeton, dimethoate, chlorpyrifas, diazinon, azinphosmethyl and phosmet; compounds which break down an insect""s digestive tract tissue including fluorine compounds (cryolite), zinc and mercury; nicotine; rotenone; neem oil or azadiractin; natural or synthetic pyrethrins, permethrin, lamda-cyhalothrin, cypermethrin, petroleum oils; and microbials e.g. bascillus thuringiensis and entomopathic viruses such as the bacculo virus.
Acaricides such as clofentezine or 3,6-bis(2-chlorophenyl)-1,2,4,5-tetrazine.
Among water soluble active materials, non-selective herbicides, particularly N-(phosphonomethyl) glycine type herbicides such as glyphosate and sulphosate, respectively the iso-propylamino and trimethylsulphonium salts of N-phosphonylmethyl glycine, and other salts such as ammonium, sodium and potassium; and phosphinyl amino acids such as glufosinate or 2-amino-4-(hydroxymethylphosphinyl)butanoic acid, particularly as the ammonium salt. Such water soluble actives can be used as the sole active in water dispersible granules or in combinations thereof, but can also be used in combination with water insoluble or immiscible actives in multi-active formulations.
The agrochemical formulation of this invention can include one or more surfactants and/or adjuvants and other additive ingredients. Surfactants have surface active properties and help to increase the dispersibility of the active material and/or can also act as an emulsifier, solubilizer, wetting agent or suspending agent. Adjuvants are materials that help to increase the biological efficacy of the active material and include surfactants, oils such as mineral oils, vegetable oils and alkyl esters of fatty acids, and combinations thereof. Other additive ingredients and materials can be used to provide a variety of functional attributes to the formulation and include materials such as buffering agents, rheological modifiers, antifoam/defoamers, drift/mist control agents, viscosifiers, emulsifiers, dispersants, suspending agents, solvents and fillers. One or more of such surfactants, adjuvants and other additves may be used and they are not limited by physical form such as liquid, paste or wax; or by being water soluble (i.e. from fully water soluble to water insoluble) or water dispersible (e.g. forming aqueous solutions, dispersions or emulsions). The surfactant or adjuvant may help increase the biological efficacy of the active material. The particular surfactant and/or adjuvants that are used in the formulation will depend on the active material and its properties.
The surfactant used in the formulation may be non-ionic, cationic, anionic, amphoteric or a blend or combination thereof. Exemplary non-ionic surfactants include alcohol alkoxylates, e.g. ethoxylates, particularly C8 to C18 alcohols which can be linear, branched or linear/branched mixtures; alkylamine alkoxylates, e.g. ethoxylates and particularly C8 to C18 alkylamines; sorbitol and sorbitan fatty acid esters, particularly C8 to C18 fatty acids esters and their ethoxylated derivatives; and chemically modified low molecular weight polysaccharides, particularly C6 to C14 alkyl polysaccharides such as alkylpoly-glycosides. Other non-ionics include polyoxyethylene-polyoxypropylene block copolymers, glycerol esters, glycol esters, alkoxylated and non-alkoxylated sorbitan esters, sucrose esters, sucrose glycerides, polyoxyalkylene alkylaryl ethers, polyoxyalkylene alkyl esters and fatty acid ethoxylates.
Cationic surfactants that are useful include primary, secondary and tertiary alkylamines, tertiary polyoxyalkylene alkylamines, polyoxyalkylene and non-polyoxyalkylene alkylamine oxides, tertiary polyoxyalkylene alklyetheramines, polyoxyalkylene alkyletheramine oxides, and tetra alkylammonium halides.
Useful anionic surfactants include alkyl sulfates and phosphates, olein sulfonates, alkylaryl sulfonates, polyoxy-alkylene alkylether sulfates and phosphates, sulfosuccinate derivatives, sulfosuccinates, sarcosinates, taurates, sulfates and sulfonates of oils.
Useful amphoteric surfactants include N-alkylbetaines, alkyl amidobetaines and imidazoline derivatives.
The selected starch component which can be used in the solid products or formulations of this invention are chemically modified starches and more particularly are starch esters and starch ethers. The starch esters and starch ethers may contain nonionic or ionic substrate groups such as cationic, e.g. tertiary amine and quaternary ammonium groups, or anionic groups, and may be crosslinked. Modified starches of these types are described in xe2x80x9cStarch: Chemistry and Technologyxe2x80x9d, edited by R. L. Whistler et al, Chapter X, 1984. Preferred modified starches are those containing an ester or ether group. The base starch may be any starch, native or converted, and includes those derived from any plant source such as maize, tapioca, potato, wheat, rice, sago, sorghum, waxy maize, waxy potato and high amylose starch, i.e. starch having at least 40% by weight of amylose content. Also included are the conversion products derived from any of the former bases including, for example, dextrin prepared by hydrolytic action of acid and/or heat; oxidized starches prepared by treatment with oxidants such as sodium hypochlorite or hydrogen peroxide; and fluidity or thin boiling starches prepared by enzyme conversion or mild acid hydrolysis.
Modified starch esters include starch acetate, starch propionate, starch butyrate, starch hexanoate etc. as well as the half-esters of dicarboxylic acids, particularly the alkenylsuccinic acids. Starch ethers include the hydroxyalkyl ethers such as hydroxyethyl and hydroxypropyl starch. The starch esters and ethers used in this invention may be prepared by processes known in the art such as disclosed in xe2x80x9cStarch: Chemistry and Technologyxe2x80x9d, noted above.
The preparation of starch esters typically involves reacting starch with organic acid anhydrides such as acetic anhydride in either aqueous or non-aqueous systems, e.g. anhydrous pyridine. A review of such preparations may be found in xe2x80x9cStarch: Chemistry and Technologyxe2x80x9d, edited by R. L. Whistler et al, Chapter X, 1984, as well as in U.S. Pat. No. 2,661,349 issued to C. Caldwell et al on Dec. 1, 1953 and U.S. Pat. No. 5,321,132 issued to R. Billmers et al on Jun. 14, 1994. The ""349 and ""132 patents are hereby incorporated herein by reference.
One modification of starch that is especially useful in this invention is a starch ester prepared from an organic acid anhydride having a hydrophobic group such as octenyl or dodecenyl succinic anhydride. More particularly, the hydrophobic group is a hydrocarbon group such as alkyl, alkenyl, aralkyl or aralkenyl having 2 to 22 carbons, preferably 5 to 18 and more preferably 8 to 12 carbons. Generally the starch will be treated with up to 60%, more particularly 1 to 60% and preferably 5 to 20% by weight of the anhydride, based on the weight of starch.
Another modification of starch that is especially useful in this invention is the etherification with alkylene oxides, particularly those containing 2 to 6, preferably 2 to 4 carbon atoms. Ethylene oxide, propylene oxide and butylene oxide are exemplary compounds that are useful in etherifying the starting starch materials. Although varying amounts of such reagent compounds may be used, generally up to 25%, more particularly 1 to 25% and preferably 1 to 10% by weight, based on the weight of starch, will be used.
The modified starches as used herein may be degraded or converted to achieve certain viscosity characteristics and allow for better interaction with components. The modified starches may also be pregelatinized or crosslinked. The degraded starches can vary from 15 to 90 WF (i.e. water fluidity). In addition, dextrins and/or multi-dextrins of  less than 10 DE (dextrose equivalent) can be used. Degradation can be carried out using conventional processes such as oxidative hydrolysis including treatment with hydrogen peroxide, enzyme hydrolysis or acid hydrolysis. Such degradation can be performed either before or after modification is made to the starch.
The important feature of this invention is being able to provide an agrochemical formulation or surfactant and/or adjuvant system in the modified physical form of a stable, solid such as a free-flowing powder. This can be accomplished when using either a water soluble active material or a water insoluble active material, i.e. emulsifiable or suspendable oily or non-water soluble active materials. This can include mixtures of two or more different active materials such as two or more water soluble or two or more water insoluble active materials or combinations thereof. The active materials do not have to be of the same physical form, e.g. liquid or solid. The ability to do this is provided by use of the selected modified starches as defined herein. The starch provides a matrix for the system and changes the physical form thereby allowing for the use of different surfactants and adjuvants including those in aqueous solutions, oils, waxes, emulsions, etc. Additionally, while previously it has been difficult to incorporate liquid surfactants or adjuvants into the formation of solid products such as powders, the use of starch as described herein, has allowed for the use of such liquids as well as solid surfactants or adjuvants.
The dry solid can be made by dissolving or dispersing the active material, surfactant and/or adjuvant in a starch cook by either mixing the components with raw starch then cooking, e.g. jet cooking, or by mixing the components into cooked starch. Raw starch is generally refined and recovered from plant tissue as microscopic semi-crystalline particles termed granules. These raw granules must be disrupted or gelatinized, usually by heating in a water suspension or slurry, to produce a colloidal dispersion, solution or starch cook. Gelatinization in water or other solvent, is required to allow the starch cook to provide film or matrix forming properties after drying. A wide range of cooking processes are generally suitable, such as, atmospheric pressure batch cooking, elevated pressure batch cooking (autoclaving), steam injection cooking (jet cooking) at either theoretical or excess steam addition ratios, or non diluting heat transfer methods. See xe2x80x9cChemistry of the Carbohydratesxe2x80x9d, by W. W. Pigman and R. M. Goepp, Academic Press, 1948, p. 561f. Pre-gelatinized starches that do not require the cooking step before adding the starch to the surfactant and/or adjuvant can also be used. The pre-gelatinized starches are readily available and can be produced by many methods such as disclosed in U.S. Pat. No. 4,280,851 issued to Pitchon et al. in July, 1981; U.S. Pat. No. 5,571,552 issued to Kasica et al. in November, 1996; U.S. Pat. No. 3,086,890 issued to Sarko et al. in April, 1963; U.S. Pat. No. 3,637,656 issued to Germino et al. in January, 1972 and U.S. Pat. No. 3,137,592 issued to Protzman et al. in June, 1964. All of these patents are hereby incorporated herein by reference. These mixtures are then dried into a solid such as powder by spray drying or using other drying techniques such as drum drying, extrusion, belt drying or freeze drying.
In a similar manner, the solid product can be made by dissolving or dispersing a) the active material, or b) the surfactant and/or adjuvant in a starch cook by either mixing the components with raw starch and cooking or by mixing the components with cooked starch or pre-gelatinized starch. These mixtures are then dried into solids such as powders using drying techniques such as spray drying, drum drying, extrusion, belt drying or freeze drying. Also, similar products can be prepared with the addition of other additive materials to the components of the above described systems.
While the form of the solid pieces resulting from the process of preparation may be in various sizes and shapes, one particularly useful form are granules which are considered dustless or have particles with sizes of between about 250 to 800 microns. An especially useful process for drying the aqueous feedstock and obtaining dust free granules of useful diameters in one process step is disclosed in U.S. Pat. No. 5,628,937 issued to Oliver et al., which is hereby incorporated by reference. Additional processing such as agglomeration, compact granulation or extrusion can be used, if desired, to attain a more specific particle size range.
The solid formulations of this invention are characterized by high loading of the active ingredient and rapid homogeneous dispersibility in aqueous medium. The amount of starch in the system can vary but generally will be less than about 85% by weight. There should be enough starch to make stable solid such as a free flowing powder.
The amount of active material and other components in the load which make up the formulation can vary. Load is defined as the total amount of active material, surfactant, adjuvant and optional other additive ingredients in the formulation. The formulation will comprise, on a dry basis, from about 15 to 85% by weight of load and from about 15 to 85% by weight of starch, more particularly from about 20 to 80% by weight of load and from about 20 to 80% by weight of starch, and most particularly from about 30 to 70% by weight of load and about 30 to 70% by weight of starch. The percent (%) load is the anhydrous (dry) weight of the load divided by the anhydrous (dry) weight of the total formulation (i.e. load plus starch)xc3x97100. The load may be comprised of from about 0 to 100% by weight of active, from about 0 to 100% by weight of surfactant and/or adjuvant, and from about 0 to 90% of other additive ingredients with the proviso that there be at least 10% by weight of active and/or surfactant and/or adjuvant with other additive ingredients. The load may also be completely comprised of active material or surfactant/adjuvant when only one of such components is present.
Any load component which is a non-water soluble liquid or meltable solid usually must be emulsified. The hydrophobically modified starches provide very useful emulsifying properties. Small particle emulsions allow higher loading of emulsified materials and remain as stable products when dried. Furthermore, smaller particle size may give increased efficacy of the active ingredients or improve the agricultural activity of the other ingredients.
The formulation of this invention as described herein may comprise more than one of the components, i.e. one or more active materials, surfactant/adjuvants and starch materials and combinations thereof. The different individual materials do not have to be of the same physical form (e.g. liquid or solid). The ability to be able to do this is due to the selected starch component which forms a matrix and helps provide a stable, compatible system even when using materials or components with different physical forms.
It is further noted that while the solid formulated product containing an active material, and/or surfactant/adjuvant in a starch matrix is a desired or preferred embodiment of this invention, this is because such solid product can be readily dispersed in water to conveniently, quickly and accurately provide a tank spray mixture for ready use in an agrochemical application. However, the components may be used separately without forming a solid or powder. Thus the individual components, i.e. active material, and/or surfactant/adjuvant can be added or combined separately in water along with the starch to form an aqueous dispersion (e.g. in a spray tank). These materials can be used in agrochemical applications or may have other uses apparent to one skilled in the art. One such application involves the combination of starch and surfactant which can be used as a soil or substrate wetting agent. The varied and different useful applications are derived in part from the starch component, which not only is useful as a matrix or solid carrier for the active material and other components but also helps to increase biological efficacy, i.e. it has adjuvant characteristics.
The aqueous dispersion, as noted above, containing starch and active material along with optional surfactant/adjuvant, can be formed by redispersing the solid product of the components or by adding the components together or separately in water. This aqueous dispersion containing the active material along with starch and optional surfactant/adjuvant has an increased biological efficacy. This makes the dispersion particularly useful as a herbicide, pesticide and plant growth regulator for applications to agricultural crops, vegetation, weeds, plants, insects, pests and soil. Particularly useful in providing biological efficacy are starches combined with glyphosate, such as glyphosate-isopropyl amine (IPA), and strobilurin, such as azoxystrobin, active materials. Especially useful combinations are starches combined with glyphosate-isopropyl amine (IPA) and polyoxyethylene sorbitan ester (Tween 20) and starches combined with azoxystrobin and non-ionic surfactants, (ethoxylated C8 to C18 alcohols).
Besides being used as a redispersed solid or by application from an aqueous dispersion, the starch containing products can also be used as a solid in dry form without dispersing in water. For example, the starch entrapped product can be broadcast onto soils as a powdered particulate or pest bait. Another embodiment of this invention involves a solid product containing a surfactant or adjuvant, particularly a non-oil adjuvant, in a starch matrix.
The water soluble starch containing solid of this invention, is a stable mixture which is compatible and quickly releases the active ingredient and adjuvants once dispersed in the spray or feed tank. These products have been found to provide a high loading of active ingredient and surfactant/adjuvant and also allow for use of a broad range of surfactant chemistries. Furthermore and surprisingly, use of these products result in beneficial properties such as increased biological activity and increased rainfastness.
The invention is further illustrated by the following examples with all parts and percentages given by weight and all temperatures in degrees Celsius, unless otherwise noted.